Waves LinMB Linear Phase MultiBand Software Audio Processor User guide

Brand: Waves

Model: LinMB Linear Phase MultiBand Software Audio Processor

Type: User guide

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Waves – Linear-Phase MultiBand

Software Audio Processor

Users Guide

version 2 Dec. 27th

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Chapter 1 – Introduction

Introducing Waves Linear-Phase MultiBand Processor.

The LinMB is an evolved version of the C4 MultiBand Parametric Processor. If

you are familiar with C4 you will find the Linear Phase MultiBand very similar,

adding some true breakthrough innovation and technology that yields superior

and purer results.

The LinMB has -

• 5 discrete bands each with its own gain and dynamics for equalizing,

compressing, expanding or limiting each band separately.

• Linear Phase crossovers allow true transparency when the split is active

but idle. The only effect is pure delay with no coloration of any sort.

• LinMB is equipped with the options for Automatic Makeup and gain Trim.

• Adaptive threshold behavior achieves most effective and transparent

multiband dynamics processing.

• LinMB has the visual interface of the award winning C4 with Waves’

unique DynamicLine™ display showing the actual gain change as an EQ

graph display.

Waves created the LinMB to answer to the most demanding and critical

requirements when Mastering any sound and genre of music.

While the Waves Masters bundle is focused to provide purist quality tools for

Mastering, there are many applications in which it may be very useful i.e.

Vocal processing, Transmission processing, Noise reduction, Track Strip.

The LinMB has a fixed amount of delay or fixed latency of about 70ms (3072

samples in 44.1-48kHz). Due to the intensive calculations required for the

Linear Phase crossover it is quite an achievement to have this work in real-

time in both TDM and Native. Much effort was put to optimize the

performance for specific CPU’s using Co processors such as Altivec on MAC

and SIMD on x86 type processors. Processing higher sample rate such as

96kHz will definitely require much more CPU then 48kHz.

MULTIBAND DYNAMICS

In MultiBand Dynamics processing we split the wide-band signal to discrete

bands. Each band is sent to its dedicated dynamics processor to apply the

desired dynamic gain adjustment or static gain. Splitting the signal has

several major consequences as follows:

• Eliminates Inter Modulations between bands.

• Eliminates gain riding between different frequency bands.

• Allows setting each band’s attack, release times scaled to the frequencies

in that band.

• Allows setting different functionality (compression, Expansion, EQ) per

each band.

For example, its possible to compress the low frequencies with longer attack

release values, at the same time expand the mid range with shorter ones,

DeEss hi-mids with much faster attack and release and boost the super hi

frequencies without any dynamics.

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MultiBand devices are especially handy when dealing with the dynamics of a

full range mix. In a symphonic orchestra as well as in a Rock n Roll band

different instruments dominate different frequency ranges. Many times the low

range dominates the whole dynamic response while the higher frequencies

are riding on top. While it is the mixer’s or composer’s job to reach a desired

balance, mastering engineers often find they need to do something about the

dynamics of the mixed source. It may be to complement it further or indeed

improve its quality, or possibly just make it as loud as possible for competitive

level, with as little degradation as possible.

LINEAR PHASE XOVERS

When the LinMB is active but is idle, it presents only a fixed amount of delay.

The output is 24bit clean and true to the source.

When we use Xovers to split a signal we like to think that they are splitting the

input signal to bands leaving everything else untouched. The truth is that any

normal analog or digital Xover introduces different amount of phase shift or

delay to different frequencies. Further dynamic gain changes will cause

further modulation of the Phase shift introduced by the Xovers. This

phenomenon was treated in C4’s phase compensated Xovers but the initial

phase shift caused by the Xovers is still apparent in C4 and in its output all

frequencies are equal to the source in Amplitude but not in Phase.

When its important to achieve as much source integrity as possible the LinMB

goes a long way and splits the signal to 5 bands maintaining a 24bit clean

starting point for applying different dynamics processing to each of the bands.

Transients are the main sonic events that benefit from Linear Phase.

Transients contain a wide range of frequencies, and are highly “Localized” in

time. A non-linear phase filter that shifts the phase differently for different

frequencies will “smear” the transient over a longer period of time. The Linear

Phase EQ will pass transients maintaining their full sharpness.

ADAPTIVE THRESHOLDS AND DE-MASKING

When a soft sound and a loud sound happen at the same time, the loud

sound has some Masking effect over the softer sound. The research of

Masking, articulated the Upward spread Masking, where loud low frequency

sounds mask higher frequency sounds. The Linear MultiBand provides a way

for each band to be sensitive to the energy in its “Masker” band. When the

energy in the Masker band is high the band’s threshold will rise to introduce

less attenuation and compensate for the masking, letting the sound in each

band come out as loud and as clear as possible. The Linear MultiBand is the

first processor to introduce this de-masking behavior, of which you can read

more in Chapter 3 of this guide.

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Chapter 2 – Basic Operation.

THE WAVES LINEAR PHASE MULTIBAND’S CONTROL GROUPS –

THE CROSSOVER FREQUENCIES -

The 4 Xover frequencies are set directly under the graph by grabbing their

graph marker or using the text button. These define the cutoff frequencies in

which the WideBand signal will be split into the 5 discrete bands.

INDIVIDUAL BAND CONTROLS -

Each band of Waves LINMB has 5 adjustable dynamics settings.

Threshold, Gain, Range, Attack, Release, Solo and Bypass. These

function similarly in most dynamics processors but in this processor they

affect the dynamics of one of the 5 bands. The Range may seem unfamiliar

and basically it is in place of the well-known Ratio, but it defines both the

intensity of gain adjustment and the limit of gain adjustment. Read more In the

next chapter.

GLOBAL SETTINGS CONTROLS -

In the Global section you can find master controls, which are ganged controls

for moving all the per band controls at once.

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Other deal with the overall processor output – Gain, Trim and Dither.

The Makeup control allows selection between manual mode and Auto

Makeup.

Finally there are 4 general compression behavior controls – Adaptive

(Explained further in the next chapter), Release – Select between Waves

ARC – Auto Release Control to a manually set release. Behavior – Opto or

Electro modes affect the nature of the release. Knee - soft or hard knee or

any value in between.

QUICKSTART

To start off, Waves provide a selection of factory presets. These can mostly

serve as good starting points for applying MultiBand Dynamics. As this is not

an effects processor the actual settings have to be program dependant and

most mastering engineers would prefer to manually set the processor and not

rely on ready made settings. The processor defaults and presets offer nice

scaling of the Time Constants Attack, Release in relation to their Band’s

Wavelength providing slower settings to lower bands and faster values to

higher. Other controls are set in the presets to provide some showcase of

possible modes and different combinations.

• Start off using the Processor defaults.

• Play Music through.

• For general MultiBand Compression first set the Range in all bands to –

6dB by dragging the Master Range control downwards. This will assure

that the gain adjustment will be Attenuation or Compression and the

maximal attenuation will not exceed a 6dB reduction.

• Now set your nominal per band thresholds. Use the peak energy in each

band to set the nominal threshold to the peak value.

• Now you can drag down the master Threshold to set the general

compression. You can choose to engage Auto Makeup after setting the

nominal thresholds and this way further threshold manipulation will

preserve relative loudness and you will hear the compression rather the

change in loudness.

• Adjust the per band gains to satisfy or qualify with your idea of “flat”

Equalization.

• Play the whole program, or at least the loudest passages and hit the Trim

button to makeup the global output gain buy the its Margin to the full scale.

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Note that this Quick Start routine is not the Golden recipe to mastering with

the Linear MultiBand, it does however provide a general type practice that

should let users new to MultiBand follow a recommended workflow. This

example only scratches the surface of possibilities with the Linear MultiBand

and there are more optional advanced features that may have implications on

the workflow method. Read on in this guide to learn about some of the special

advanced features.

Generally it’s important to remember that while the process is applied to split

discrete frequency bands, it affects the Whole WideBand sound. Soloing each

band and applying its compression in solo and then listening to the whole may

prove unrewarding as a workflow.

Frequency Analyzers can be used to get visual feedback to validate or

articulate what you hear but its most important to use the ears and work in a

good listening environment for critical reference.

Practice Makes Perfect!

This tool presents a lot of choice. Its not the Renaissance tools that help you

save time for great results. It’s a highly flexible, ultra professional, purist

quality tool.

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Chapter 3 – Specialties of the Chef

ADAPTIVE THRESHOLDS AND DE-MASKING.

The effect of louder sounds on softer sounds has been researched for

decades. There are many classifications to masking and the most effective

masking is considered forward in time and upward in frequency. Simply put

loud lower frequencies affect the way we perceive higher softer frequencies.

The loud low frequency mask the higher frequencies. In the LinMB we can

consider each band to be the masker for the band above it, so when the

sound in a certain band is very loud it will have some masking effect to the

sound in the band above it. To address this we can introduce a little lift to the

threshold of the masked band and as result it will get less attenuation and be

a little louder or de-masked.

The Linear Phase MultiBand processor lets each band be sensitive to the

energy in the band below it. The “Adaptive” control is a continuous scale of

sensitivity to the Masker scaled in dB’s. –inf. Adaptive = off, this means no

sensitivity and the threshold is absolute regardless of what’s happening in the

lower band. When increasing the value the band will become more and more

sensitive to the energy in the band below it, The energy ranges from –80dB tp

+12. We call 0.0dB Fully Adaptive and values above it are Hyper Adaptive.

When the energy in the Masker band is high the threshold will be lifted. When

the energy in the lower band falls, the detail is revealed, threshold goes back

down and the attenuation goes back to normal. Also there is a chain reaction

that makes for subtle general looseness of compression to the higher bands

whenever the low bands are with high energy.

Each band of the linear MultiBand has its own compression settings and the

engineer may want to compress more when a band is exposed and less when

its masked. In example a song starts with a solo vocal and then the Playback

comes in and the picture changes. The “presence” frequencies of the voice

become more significant then the lower “Warm” tones of the voice, so to

regain warmth we would want to attenuate it less when the playback kicks in.

This is a macro example that can easily be treated with a bit of automation but

in concept masking happens on the micro scale throughout the program. For

example a staccato bass line masks and exposes the higher band’s sound on

a scale where manual riding isn’t practical. The adaptive behavior is the

practical answer.

The Adaptive De-Masking behavior is new to almost all users, and some may

think it’s unnecessary. It is however interesting, effective and worth a try.

Others may find it useful but it may also call for some practice before you get

comfortable with it. Optionally, it may change they way you work.

As a first step, try to add adaptive behavior to ready made settings on material

that you know very well. Set the Adaptive control to –0dB at this setting you

will get very adaptive behavior. Do a bit of an A > B listening test. Try to pay

special attention to passages that have different spectral dynamic nature and

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hear how the adaptive behavior responds to them adding a more dynamic

approach to dynamics. This example is somewhat extreme and it is

recommended to try settings around –12 dB for subtle adaptive de-masking. It

may also be interesting to lower the overall threshold of the top 4 “Adaptive”

bands by Multi-selecting their thresholds and pulling them down to

compensate for the added looseness, In any case when they are exposed

they will be tighter and Looser when masked.

AUTO MAKEUP

When Applying compression adjusting the threshold reduces loudness.

Indeed in most compressors we can hear the overall gain reduction and we

can apply makeup gain to regain the lost loudness.

In WideBand compressors we find auto makeup to be fairly straightforward.

The auto makeup will boost by the reverse value of the Threshold, or

sometimes have a threshold dependant makeup “range” that accounts for the

knee and ratio too. In MultiBand there are other considerations. The bands

energy is going to be summed with that of the other bands so it’s hard to

predict the part of the discrete band’s energy on the summed WideBand

signal.

The Auto Makeup in LinMB is somewhat similar in that it accounts for the

Threshold, Range and Knee. In wide band we would use the headroom to

boost the loudness further then was possible before compressing. In the

MultiBand case It is designed to help maintain general level stability for better

a/b comparing. While in a wideband compressor the overall level will be

reduced in the LinMB only the gain of a certain band will be reduced in

relation to the others. It is much easier to hear the lost loudness then the

actual compression so working with Auto Makeup the bands level remains

similar and you can focus better on the sound of the dynamics process for

that band. You can choose to use Auto Makeup as a work mode to help get

the per band compression to sound right, Then apply per band gain on top of

it. When disengaging Auto Makeup its effect will be updated into the per band

gains. It is recommended to first set nominal thresholds per band to the peak

energy in each band. Then engage auto makeup and continue to adjust the

desired dynamics.

Auto Makeup does not interfere with the per-band Gain control. Also it cannot

be clipping proofed and the overall Output gain will serve to trim the margin

between the peak and the full scale.

WAVES ARC



 - AUTO RELEASE CONTROL

Waves ARC was designed and debuted in the Waves Renaissance

Compressor. This routine sets the optimal gain adjustment release time by

being program sensitive. The Auto Release Control still refers to its band’s

release time and optimizes it according to the actual attenuation assuring

maximal transparency. Before ARC there was always a need to trade

between grainy Distortion with short release times to Pumping when setting

longer release times. ARC helps lower the extent of these artifacts. For best

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results, you may set your release time for the best compromise between

Distorting and Pumping and then apply ARC to get even better results with

less artifacts. Alternatively you can just count on this technology, set your

release value to the desired ballpark or stick with the release scaling from a

preset and rely on ARC to get it right. ARC was so well accepted wherever we

introduced it and in the LinMB it is ON by default.

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Chapter 4 – LinMB Controls and Displays.

CONTROLS

Individual Band Controls

THRESHOLD.

0- -80dB. Default – 0.0dB

Defines the point of reference for that band’s energy. Whenever the energy in

a certain band exceeds the threshold gain adjustment will be applied. For your

convenience, each band has an energy meter for visual adjustment of the

Threshold

GAIN.

+/- 18dB. Default 0.0dB

Sets the overall output gain of the band or the bands makeup value. This Gain

control can be use to adjust the gain of the band even without any dynamics

like an EQ. It is also used to adjust gain of the band that’s being compressed

or expanded to make up for the headroom created buy the compressors

attenuation, or make down to prevent clipping.

RANGE.

–24.0dB – 18dB. Default –6dB

Sets the possible range of the dynamic gain adjustment and also its intensity,

replacing the classic “Ratio” control and adding a firm boundary to it. Negative

Range means that when the energy exceeds the threshold a gain reduction

will be applied, while positive Range means boosting it further. Read more

about range in the next chapter.

ATTACK.

0.50 – 500ms. Defaults scaled for each band.

Defines the time it will take to apply the gain reduction from the moment the

detected energy exceeds the threshold.

RELEASE.

5 – 5000ms. Defaults scaled for each band.

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Defines the time it will take to release the applied gain adjustment from the

moment the detected energy falls below the threshold.

SOLO.

Solo’s the band to the main processors output for monitoring the band-pass

by itself or along with other soloed bands.

BYPASS.

Bypasses all processing on the band and sends it to the main output the

same way it was input. This allows to monitor the processed output vs. the

source for each band by itself.

Crossovers – Xover

There are 4 Crossovers in the liner multiband. Each sets the cutoff frequency

for the High Pass and Low Pass filters that cross each other.

For the calculation intensive nature of the Finite Impulse Response filters the

Xover controls will sound a click when they are reset to a new position. When

using the mouse to adjust the frequency or when grabbing the markers at the

bottom of the Graph, the new filter will be set only when the mouse is

released to avoid zipper noise. Using the arrow keys or control surface you

can advance step by step to fine tune your Xover position. Smooth sweeps

are impossible but the focus should be to set the Xover positions to the

desired cutoff frequency.

Each of the four Crossovers has a unique range of frequencies as follows:

LOW: 40Hz – 350Hz. Default – 92Hz.

LOW MID: 150Hz – 3kHz. Default – 545Hz.

HI MID: 1024Hz – 4750kHz. Default – 4000Hz.

HI: 4kHz – 16kHz. Default – 11071Hz.

Output Section

GAIN –

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Sets the overall output gain. The double precision process assures no input or

internal clipping so this gain is used at the output to prevent clipping.

TRIM –

The Auto Trim button updates the peak value and when clicked it adjusts the

output gain control to trim the margin so that the peak will equal the full digital

scale. For precise clip prevention let the program or at least its high gain parts

pass through. When clipping occurs the clip light will light up and the Trim

control box will update the peak value. Now click the Trim button to lower the

gain by the peak value.

DITHER –

The double precision 48bit process can handle overflows. The result however

comes out at 24bit back to the host application’s audio buss. Some native

Hosts may output 32 Floating point output to the mixer or to the next plug-in,

this is the only case where we would recommend not to use the dither. The

Dither control adds dithering back to the 24th bit rather then just rounding

which will be the case when the Dither is off. The dither’s noise and suspected

quantization noise when with no dither, will be very low. The dither however

can let your 24bit result virtually have a perceived 27bit resolution. Any

introduced noise will be further boosted by Limiting the output (With L2 off

course) so we did not want to commit the users to the dither noise and allow it

to be turned off.

In any case, the noise may prove to be well beneath the program’s floor and

audible only at extreme monitoring levels, tucked within the noise floor of the

reinforcement system. Normalizing dithered silence may boost the dither to

terrible noise that is completely out of context. When analyzing non dithered

silence it should remain quite silent, but this does not mean this mode is

superior. The Dither is on by default and its use is recommended unless you

know your host passes 32bit audio back to the host.

Global Behavior Settings

These settings will apply global dynamics process behavior which will

influence the per band compression properties.

ADAPTIVE:

-inf.=Off – +12dB. Default – off.

The Adaptive control sets the sensitivity of a band to the energy in its Masker-

the band below. The control uses a dB scale. The behavior will be that when

there is high energy in a certain band the threshold will be lifted for the band

above it to de-mask it. Read more about Adaptive Thresholds and de masking

in chapter 3.

RELEASE:

ARC or Manual. Default – ARC.

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The Auto release control sets an optimal release time in relation to the manual

release time. When Manual release is selected then the release of the

attenuation will be absolute as indicated, Adding ARC will make the release

sensitive to the amount of attenuation and set the best release time to get

more transparent results.

BEHAVIOR:

Opto or Electro. Default – Electro.

•Opto is a classic modeling of opto-coupled compressors which used light

sensitive resistors to control the amount of compression (in the detector

circuit). They have a characteristic release behavior of “putting on the brakes”

as the gain reduction approaches zero. In other words, the closer the meter

comes back to zero, the slower it moves. (This is once the gain reduction is

3dB or less). Above 3dB of gain reduction, the Opto mode actually has faster

release times. In summary, Opto mode has fast release times at high gain

reduction, slow release times as it approaches zero GR. This can be very

beneficial for deeper compression applications.

•Electro is a compressor behavior invention by Waves, in that it is very much

the inverse of the Opto mode. As

the meter comes back to zero, the faster it moves. (This is once the gain

reduction is 3dB or less). Above 3dB

of gain reduction, the Electro mode actually has slower release times, much

like a mini-leveler, which minimizes distortion and optimizes level. In

summary, Electro mode has slow release times at high gain reduction, and

progressively faster release as it approaches zero GR. This has very good

benefits for moderate compression applications where maximum RMS

(average) level and density is desired.

KNEE:

Soft =0 – Hard=100. Default - 50

This Master control affects all 4 bands’ knee characteristics, ranging from

softer (low values) to harder (higher values). At the maximum value, the

Master Knee control tends to give the sound a harder edge, with a punchier

overshoot-style character. Adjust to taste. The Knee and Range together

interact to give the equivalent of a ratio control. To achieve limiter-type

behavior, use high Knee settings.

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DISPLAYS

THE MULTIBAND GRAPH:

The MultiBand graph is like an EQ graph showing Amplitude in the Y-axis and

Frequency in X-axis. In the Middle of the graph resides the DynamicLine

that shows the per band gain adjustment as it happens within the Range,

represented by the Bluish highlight. Beneath the graph there are the 4

Crossover frequency markers and on the graph there are 5 markers that allow

you to set the gain of the band by dragging up and or down and the band’s

width by dragging sideways.

THE OUTPUT METERS:

The Output meters show the master output of the processor. Under each

meter there is a peak hold indicator. The Trim control under the meters shows

the current margin between the peak and the full scale. The holds and the

Trim value are reset when clicking in the meters area.

BAND THRESHOLD METERS:

Each Band has its own meter showing the input energy in that band. Under

the meter is a peak hold numeric indicator. When you want to set your

nominal thresholds you can use the peak as reference and then continue to

set them with the master threshold control.

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Chapter 5 – Range and Threshold Concept

The concept of ‘Threshold’ and ‘Range’ instead of the traditional ‘Ratio’

control creates some very flexible and powerful uses for the LINMB. They

include low-level compression and expansion, giving you multiband “upward

compressors” and noise reducers.

OLD SCHOOL / ANOTHER SCHOOL

In the classic compressor approach, if you set a very low Threshold with any

given Ratio, extreme amounts of gain reduction of high level signals may

occur. For example, with a Ratio of 3:1 and Threshold of –60dB will result in a

–40dB gain reduction for 0dBFS signals. Such a case is rarely desirable, and

in general you would only set such a low Threshold in a typical compressor

when the input level is also very low. In common practice, more than -18dB of

gain reduction or +12dB gain increase is rarely needed, especially in a

multiband compressor.

In the LINMB, the concept of ‘Range’ and ‘Threshold’ comes in very handy. It

lets you first define the maximum amount of dynamic gain change using the

‘Range’ control, and then determine the level around which you want this gain

change to take place using the ‘Threshold’. The actual values of these

controls depend on the type of processing that you want.

If Range is negative; you’ll have downward gain change.

If Range is positive; you’ll have upward gain change.

The real flexible fun happens when you offset this dynamic Range with a fixed

Gain value.

HIGH-LEVEL COMPRESSION

High-level compression in C1. Ratio is 1.5:1, Threshold is -35. Equivalent

LINMB setting would have Range set to about -9dB, with Gain set to 0.

If you are interested in conventional compression (termed here ‘high-level

compression’ because the dynamics of the compression happens at high

levels), simply set the Threshold to high values, between –24dB and 0dB, and

the Range to a moderate negative value, between –3 and –9. In this way the

gain changes will take place at the upper part of input dynamics — just like a

normal compressor will do.

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HIGH-LEVEL EXPANSION (UPWARD EXPANDER)

An upward expander from the C1, with a ratio of 0.75:1, Threshold at -35.

Equivalent LINMB setting would be a Range of +10 or so, quite a bit more

than you’d probably ever need. Shown only for clear example.

To make an upward expander (an “uncompressor”) to restore overly quashed

dynamics, simply reverse the Range setting. Make the Range be a positive

value, say between +2 and +5. Now whenever the signal is around or above

the Threshold, the output will be expanded upwards, with a maximum gain

increase of the value of Range. In other words, if Range is +3, then the

maximum expansion will be 3dB increase.

LOW-LEVEL COMPRESSION

The low-level processors are where we start to have even more fun. By using

the fixed Gain control to offset the Range, you can affect only the lower-level

signals.

If you are interested in increasing the level of soft passages, but leaving the

louder passages untouched, (termed here ‘low-level compression’), set the

threshold to a low level (say –40 to –60dB). Set Range to a small negative

value, such as -5dB, and set Gain to the opposite value (+5dB). The audio

around and below the Threshold value will be “compressed upward” a

maximum of 5dB, and the higher audio levels will be untouched, including

their transients.

This will cause high levels signals (i.e. that are significantly above Threshold)

to have no gain Change – since at high levels the Range and Gain controls

are opposite values and together they equal unity gain. While around and

below the Threshold, the Range is increasingly “inactive” and therefore

approaches a zero-gain value. Gain is a fixed value, so the result is that the

low level signal is increased by the Gain control, achieving the so-called

“upward compression” concept.

This is very clear when you see this behavior on the LINMB display. Simply

look at the yellow DynamicLine while the input signal is low or high, and see

the resulting EQ curve. In a multiband compressor application, this low-level

compression is very handy to create a dynamic ‘Loudness Control’ that could

boost the LOW and HIGH bands only when their levels are low, as just one

example.

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Upper line shows Low-level compression (upward), achieved when Range is

negative and Gain is equal but positive. Lower line shows Low-level

expansion (downward), achieved when Range is positive and Gain is equal

but negative. Graph is taken from C1 to help visualize the gain structures in

the LinMB.

LOW-LEVEL EXPANSION (NOISE GATE)

If you are interested in a noise gate for a particular band or bands, set Range

to a positive Value, Gain to the inverse of the Range, and Threshold to a low

value (say -60dB). Similar to the above example, at high levels the full

dynamic gain increase set by the Range is retained, and is fully compensated

for by the Gain. While around and below the Threshold, the dynamically

changing gain comes closer to 0dB, and the result is that the fixed negative

Gain is applied to the low level signal — which is also known as gating (or

downward expansion).

“UPSIDE DOWN” THINKING

These low-level examples may seem a little inverted to what you would

expect. For instance, that a noise gate would have a positive Range.

If you just remember that when the signal goes around the Threshold, then

the Range becomes “active”, and that the Threshold is the halfway point of

the Range. So whether Range is +12dB or –12dB, then audio 6dB above and

6dB below the Threshold is where the “knees” of the dynamic change will

occur.

Positive Range

Then, if Range is positive and Gain is set to be the negative of Range

(opposite but equal), then around and above the Threshold all audio will be a

0dB gain (unity). Below the Threshold, the Range is not active, so the Gain

(which is negative) “takes over” and reduces that band’s gain. This is what

gives the downward expansion.

Negative Range

Another seeming example of the “upside down” concept is that low-level

compression takes a negative Range. Again, remember that in the LINMB,

whenever the audio is around the Threshold, the Range is active. So, if we set

Range to negative, anything around or above the Threshold can be reduced

in gain. However! Here’s the tricky part: if we set Gain to perfectly offset the

Range value, then everything well above the Threshold has no effective gain

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change at all, which means everything well below it gets “lifted up”. (If you

take this just a bit further, you’ll figure that all audio exactly at the Threshold

will have half of the Range’s value in positive gain).

ONE MORE WAY TO THINK ABOUT IT

Here is another bit of help so that you can really learn and use the power of

the LinMB to its fullest capability. We’ll take another example from the Waves

C1 Parametric Compander, our one-band processor (it also does wideband

and sidechain). It has a typical ratio and makeup gain control and has been

widely used for upward compression (both wideband and split-band

parametric usage).

The Linear MultiBand Parametric Processor has a very similar compressor

law as the Waves C1 and the Waves Renaissance Compressor. This model

allows the “compression line” to return to a 1:1 ratio line as the level continues

to increase. In other words, there is no compression of the low signal,

compression around the Threshold, and once the signal goes quite a bit past

the Threshold, the compression tapers off back to a 1:1 line (no compression).

In the graphic shown, you can see this exact type of line. The ratio is 2:1 and

the Threshold is –40dB. The line is just curving a bit (-3dB down point) at the

–40 input (the scale at the bottom). Output level is the scale on the right

vertical edge, and you can see that at about –20dB, the line starts curving

back to a 1:1 line.

So, very high-level audio peaks between 0 and –10dBFS are not touched at

all, audio between –10 and –40 is compressed, and audio below –40 is not

compressed, but is clearly louder at the output than at the input. This is low-

level compression, or “upward compression”. Such a trick is very useful and

has been implemented by classical recording engineers, mastering houses,

and classical broadcasting. Low-level compression can “lift” soft sounds up

gently and leave all the high-level peaks and transients completely untouched,

reducing the dynamic range from the bottom upwards.

We did say that the LinMB was “very similar” to the C1, but different in a

significant way: the Threshold defines the midpoint of the Range. Therefore,

to achieve the same curve in the LinMB as shown here, the Threshold on the

LinMB would actually be about –25 with a Range setting of +15.5dB. Now this

is a very large amount! The example shown here was merely to make it

obvious; we picked the 2:1 line only because it is easier to see on the page. In

reality, low-level compression that lifts the softer audio up 5dB is equivalent to

an approximate ratio of 1.24:1. Lifting the low-level up about 5dB is a good

Waves LinMB software guide page 19 of 28

example for several reasons. It is (1) a very realistic setting that could be

equal to what is being done by the previously mentioned engineers; (2) only

raising the noise floor by an acceptable amount for many applications; (3)

easy to hear on nearly any type of audio, not only classical. In the Load menu

of the LinMB are a few factory presets with names beginning “Upward

Comp…” that are good points to learn more about this concept. More presets

are in the LinMB Setup Library.

In the next chapter there are more specific examples of using low-level

processing (compression, expansion) that are very good starting points as

well as models for learning.

Waves LinMB software guide page 20 of 28

Chapter 6 – Examples of use

PRACTICE OF MULTIBAND AND MASTERING

Upon a time the mediums just couldn’t handle the same dynamic range that

an orchestra can produce or a Microphone transduce, so for the lower

passages not to be too low and the peaks not too high, compression and peak

limiting was used. In broadcasting AM signals, the hotter the signal was the

further it would reach. Since heavy wide-band compression causes

modulation distortions these industries used EQ Xover filters to split the signal

and feed it into separate compressors and then mix back. Today’s mediums

for both transmission and local music playback have a dynamic range that is

quite fit to carry extreme dynamics, yet compressors are still heavily used in

most cases and in some to an extreme extent.

We find that nowadays the Mastering stage is where broadband signals are

processed with compression for best translation from the low noise

professionally equipped mixing environment to the hi fi home systems,

personal headphone players or car reproduction systems. At this stage it is an

art of subtlety to complement a ready-made mix while effectively taking

advantage of the target media properties and the typical target reproduction

properties to reach a certain optimum.

The master will be the carrier of the so-called “Flat” response of the program

material. This “Flat” response may well be further processed at the listener’s

side for boosting or cutting frequency ranges according to taste driven

preferences. While we can reach relative flatness with EQ devices, it may

sometimes be complementary and perhaps necessary to add some frequency

range dependant push or pull to fit even better. It’s like putting the mix on

vitamins, making it as potent as possible in all frequency ranges to cut

through best at any given playback scenario.

It is recommended to apply MultiBand dynamics as a first generation of

mastering compression before applying another stage of wide band limiting.

This way more transparency will be maintained for a similar amount of

loudness gained. The MultiBand stage will serve to optimize the dynamics of

the broadband signal for that final stage. As indicated before it is a subtle

trade. The taste and experience of the mastering engineer will determine the

result and the Linear MultiBand may serve as a purist level tool offering total

transparency when splitting the signal to 5 discrete bands for the engineer to

do he’s thing.

That aside, we recommend trying the Multiband Opto Mastering

preset, or the Basic multi preset. Either one will give you reasonable

compression and increased density of your mix.

To enhance low-level signals (a great way to boost level without squashing

dynamics), try the Upward Comp +5, or +3 version of the preset. This is

great for adding level without losing punch.

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Waves LinMB Linear Phase MultiBand Software Audio Processor User guide

Waves LinMB Linear Phase MultiBand Software Audio Processor User guide

Waves LinMB Linear Phase MultiBand Software Audio Processor User guide

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